1. Field of the Invention
This invention relates to novel pharmaceutical uses of bilobalide and derivatives thereof, and to pharmaceutical compositions adapted for such use.
2. Description of Related Art
Bilobalide is a sesquiterpene of formula ##STR1## which may be extracted from leaves of the tree Ginkgo biloba.
Bilobalide was first isolated from the leaves of Ginkgo biloba and chemically analysed in 1969 (K. Weinges, Liebigs Ann. Chem. (1969) 724, 214 and K. Nakanisshi, J. Am. Chem. Soc., (1971) 93, 3544).
Recently various medical applications have been proposed for bilobalide in the treatment of pathological conditions of the nervous system. For example U.S. Pat. No. 4,892,883 and EP-A-0 143 977 describe the pharmacological use of bilobalide in the treatment of neuropathies, inflammatory conditions and immunodeficient and neurological conditions of traumatic origin. EP-A-0 441 279 describes the use of bilobalide derivatives, particularly complexes with phospholipids, in the treatment of peripheral disorders associated with inflammatory and neurodystrophic alterations.
No other useful biological effects have been reported and, in fact, EP-A-0 143 977 specifically states that bilobalide has no antifungal action against Monilia fructicola or Penicillium glaucum and no antibacterial action against Escherichia coli.
It is thus extremely surprising that following an extensive investigation of the biological properties of bilobalide, it has been found that bilobalide and derivatives thereof may be used in the treatment of infections with pathological strains of a variety of diverse pathogenic bacterial, fungal and protozoal organisms.